<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <script src="../react18/react.development.js"></script>
  <script src="../react18/react-dom.development.js"></script>
  <script src="../react18/babel.min.js"></script>
  <script src="../react18/prop-types.js"></script>
</head>

<body>
  <div id="app"></div>
  <script type="text/babel">

    class App extends React.Component{
      constructor(){
        super();

        console.log("****constructor:创建组件时的构造器函数****");
      }


      UNSAFE_componentWillMount(){
        console.log("****componentWillMount:组件即将挂载****");
      }

      render(){
        console.log("****render:组件挂载中****");
        return <h1>挂载流程</h1>
      }

      //常用:!!!!:主要用户执行组件初始化的操作:比如ajax请求,定时器,订阅等
      componentDidMount(){
        console.log("****componentDidMount:组件挂载完成****");
      }
    }

    const root = ReactDOM.createRoot(document.getElementById('app'));
    root.render(<App/>)

  </script>
</body>

</html>